In present computer systems, a computer user may introduce information into or delete information from a document, such as, for example, a word processing or spread sheet document, and select the position in the document where the insertion or deletion is to occur, by physically depressing the appropriate keys on a keyboard or other similar keystroke device which is connected in a conventional manner to a microprocessor unit in the computer system. A cursor displayed on a video display terminal which is typically attached to the microprocessor unit provides a visual display of the document to assist the user in performing the desired keystroke sequences associated with editing and cursor movement in the document.
During the course of editing a document, a computer user frequently executes similar keystroke sequences, each of which involve the repeated depression of an individual key on the keyboard. For example, the user must physically depress the right arrow key, ".fwdarw.", on the keyboard a multiplicity of times each time that the user desires to move the cursor a few spaces to the right within the same text line. A keyboard macro or function key is neither practical nor useful for reducing the number of keystroke depressions performed in common editing tasks, such as, for example, moving the cursor from ten to twenty places along the same text line or adding ten to twenty blank lines to a document.
Currently, some computer systems are being manufactured to include speech or voice recognition capabilities in the microprocessor unit. These systems allow the user to utilize voice commands for performing certain editing and cursor movement tasks without executing a repetitive keystroke sequence on a keyboard.
The implementation of voice recognition technology in a computer system not originally manufactured with voice recognition capabilities, however, typically will require that high cost memories be added to the microprocessor unit to satisfy the software needs associated with voice recognition application programs. Furthermore, additional hardware such as a microphone, speech processor and a suitable input to the microprocessor unit typically must be added to an older computer system in order to provide for the capability of speech recognition.
Thus, owners of these older computer systems presently cannot take advantage of voice recognition techniques for operating on a document without incurring the high cost and inconvenience of purchasing a new system or upgrading the capabilities of their existing systems. Therefore, a need exists for a low cost apparatus that may be easily installed in older computer systems which were not originally fabricated with the necessary features required for performing voice recognition and which could not perform voice recognition tasks without the addition of new connections and components.